Robots are increasingly being used in many industrial applications to transport articles from one location to another. Sequential lifting and placing of articles can easily be accomplished by robots to free manual labor from such tedious and boring tasks. Moreover, robots can effectively operate in dirty, hot and even hazardous locations where environmental conditions would otherwise limit or preclude the use of a human operator. There are additional advantages to using robots for article handling. Robots can be programmed to sequentially pick and place articles with extremely high positioning accuracy, thereby increasing manufacturing productivity. Further, robots can operate unattended, permitting their use at night or on weekends.
Present day article handling robots, although they differ as to their specific construction, generally include an articulated arm whose individual segments are each movable about a separate axis along a preprogrammed path. Electric, hydraulic or pneumatic motors are provided to move each segment of the articulated arm under the control of a robot control system. A robotic hand or gripper is provided at the end of the arm for gripping the article to be transported by the robot. In the past, robotic hands have been designed for gripping a single article. Thus, to transport an array of articles, the robot must individually pick and place each article of the array in sequence. Piecemeal transportation of the articles of the array in this fashion is time consuming and inefficient.
Accordingly, there is a need for a technique for batch pickup of articles arranged in an array.